“Amateurish” remains a pejorative but “amateur” comes from the Latin amare, which means "to love," making amateurs people who do things for the love of doing them. And, paraphrasing Walt Willis, those who hold that professionals are invariably superior to amateurs are doomed to prefer the ministrations of gigolos and prostitutes to those of willing and imaginative lovers.

Amateur journalism. This usually refers to the hobby as carried on by the mundane amateur press associations. Fans sometimes use it when asked what their hobby is by someone who wouldn't understand what fandom] is; and indeed, fan activity is amateur journalism — plus.